Process for the preparation of a syndiotactic polyolefin

摘要

A syndiotactic polyolefin is obtained in a high yield by polymerization or copolymerization of an olefin of the formula Ra-CH=CH-Rb in the presence of a catalyst consisting of a metallocene of the formula I (I) in which M1 is titanium, zirconium, vanadium, niobium or tantalum, and an aluminoxane. This polyolefin has a very high molecular weight, a very narrow molecular weight distribution and a very high syndiotactic index. Shaped articles produced from the polymer are distinguished by a high transparency, flexibility, tear resistance and an excellent surface gloss.